Question

If a+b=14 and ab=45 then find out the value of a^2+b^2

Answer 1

Answer:

$a + b = 14$

$squaring \: on \: both \: sides$

$(a + b) {}^{2} = 196$

$a {}^{2} + b {}^{2} + 2ab = 196$

$a { }^{2} + b {}^{2} = 196 - 2 \times 45$

$a {}^{2} + b {}^{2} = 196 - 90$

$a {}^{2} + b {}^{2} = 106$

Answer 2

Answer: 106

Step-by-step explanation:

$(a+b)^2 = a^2+b^2+2ab$

Using this identity, put the values of a+b = 14 and ab = 45

$(14)^2=a^2+b^2+2(45)$

$196 =a^2+b^2+90$

$a^2+b^2=196-90$

$a^2+b^2=106$

Hope it helps you.